大脑中动脉梗死患者运动功能的恢复与脉络丛前动脉供血脑区有关？

no chinese abstract     

The anterior choroidal artery does not supply the corona radiata and lateral ventricular wall

BACKGROUND AND PURPOSE: We sought first to characterize the clinical syndromes of patients found to have angiographic, computed tomographic, or magnetic resonance imaging scan indexes of anterior choroidal artery territory infarction and then to determine the frequency of involvement of the periventricular corona radiata in such patients. METHODS: Sixteen patients were selected based on angiographically, or surgically, documented occlusion of the anterior choroidal artery or based on infarcts whose minimal lesions included the anterior choroidal territory as defined by Kolisko and Beevor. We mapped the lesions using the templates of the Matsui and Hirano atlas and entered them into a computer using a program allowing overlapping diagrams of the cases. RESULTS: The anatomic distributions were fairly uniform, all involving the lower portion of the posterior limb of the internal capsule, the medial pallidum (75% of cases), cerebral peduncle in 44%, thalamus in 37%, and the medial temporal lobe in 38%. None extended outside these areas to include the upper corona radiata. The clinical picture corresponded to the well-established neurological syndrome featuring motor deficits with varying degrees of visual field and sensory impairments. Only two showed hypesthetic ataxic hemiparesis. CONCLUSIONS: Our findings indicate that the syndrome of anterior choroidal artery infarction is fairly uniform; ataxic hemiparesis occurs infrequently; and lesions in the lateral ventricular wall and the corona radiata are not part of the territory supplied by the anterior choroidal artery.     

Ipsilateral hemiparesis caused by a corona radiata infarct after a previous stroke on the opposite side

Ipsilateral hemiparesis after a supratentorial stroke is rare. However, the role of the reorganization of the unaffected hemisphere in recovery after a stroke is poorly understood. Two patients developed ipsilateral hemiparesis after a left corona radiata infarct. Both of these patients had previously experienced contralateral hemiparesis after a right-sided supratentorial stroke. Functional magnetic resonance imaging demonstrated bilateral motor area activation during paretic left hand movement. This finding suggests that the ipsilateral hemiparesis was caused by a new stroke in the ipsilateral motor system that was functionally reorganized after the previous stroke.     

Deterioration of pre-existing hemiparesis brought about by subsequent ipsilateral lacunar infarction

Mechanisms of post-stroke recovery are still poorly understood. Recent evidence suggests that cortical reorganisation in the unaffected hemisphere plays an important role. A 59 year old man developed a small lacunar infarct in the left corona radiata, which then caused marked deterioration in a pre-existing left hemiparesis that had resulted from an earlier right putaminal haemorrhage. Functional magnetic resonance imaging showed that the paretic left hand grip activated the ipsilateral left motor areas, but not the right hemispheric motor areas. This suggests that partial recovery of the left hemiparesis had been brought about by cortical reorganisation of the left hemisphere and intensification of the uncrossed corticospinal tract. The subsequent small infarct may have damaged the uncrossed tract, thereby causing the pre-existing hemiparesis to deteriorate even further.     

Cheiro-oral syndrome due to lesions in the corona radiata.

BACKGROUND AND PURPOSE: We describe three patients with cheiro-oral syndrome caused by a small lesion in the corona radiata confirmed by high-resolution magnetic resonance imaging. CASE DESCRIPTIONS: Case 1: A 56-year-old hypertensive man who developed hypesthesia and paresthesia in the left perioral area and hand was found to have a small hematoma just lateral to the right internal capsule. Case 2: A 67-year-old man noticed hypesthesia around the left mouth angle and thumb and index finger. Magnetic resonance imaging revealed a lesion in the right corona radiata. Case 3: A 45-year-old hypertensive man developed numbness in his perioral region and left hand that later spread to his shoulder. Magnetic resonance imaging revealed a recent small infarct in the lower lateral aspect of the right corona radiata. CONCLUSIONS: A small lesion in the corona radiata can cause cheiro-oral syndrome, whose pathogenetic mechanism in such patients may be explained by the somatotopical location or by the differing vulnerability of the neuropils in the corona radiata.     

Subacute Methotrexate Encephalopathy Mimicking Ischemic Stroke With Dynamic Changes on Magnetic Resonance Imaging

We report a 35-year-old woman who suddenly developed left hemiparesis and dysarthria at 13days after treatment with intrathecal and intravenous methotrexate for intravascular large B cell lymphoma with possible central nervous system infiltration. Seven hours after onset, she developed further right hemiparesis and aphasia. However, the majority of neurologic symptoms disappeared spontaneously and completely by 34hours. We also recorded the dynamic progression and regression of abnormal signals in the bilateral corona radiata on diffusion-weighted imaging, in parallel with neurologic symptoms. The rapid reversal of MR abnormalities and neurologic symptoms allowed us to diagnose methotrexate encephalopathy, and exclude intravascular large B cell lymphoma recurrence and regular brain infarction. The case provides new data on the dynamic changes of abnormal signals on magnetic resonance imaging in methotrexate encephalopathy over a short recovery time.     

表现为孤立性眩晕的大脑中动脉穿支梗死

目的孤立性眩晕主要见于前庭周围性病变,罕见于大脑中动脉(MCA)穿支脑梗死,本文探讨MCA穿支梗死出现孤立性眩晕与头晕的临床特征。方法报道3例表现为孤立性眩晕和头晕的MCA穿支急性腔隙性脑梗死患者的临床表现、影像学资料,同时通过PubMed检索之前报道的病例,回顾总结其临床特征。结果包括文献共5例表现为眩晕和头晕的MCA穿支梗死病例。3例表现为孤立性眩晕和头晕,1例表现为持续性头晕伴随短暂性言语不清,1例有轻偏瘫,2例有眼球震颤。眩晕与头晕严重程度均为中度,经治疗后眩晕和头晕多在病程7 d内完全缓解。4例梗死灶位于左侧内囊或放射冠区,1例位于右侧放射冠。颈部及头部增强血管成像有2例显示右侧椎动脉纤细狭窄,4例完成了头部增强CTA检查均提示前循环血管正常。本文3例患者在核磁共振成像(MRI)检查证实为急性腔隙性脑梗死之前,均未有明确诊断。结论 MCA穿支脑梗死可以表现为孤立性眩晕和头晕,严重程度较轻,持续时间通常数日,自主神经症状不明显。为了避免漏诊或误诊,推荐神经影像学检查,特别是MRI弥散成像(DWI)可作为老年首次眩晕和头晕的常规检查项目。     

Early ischemic lesion demonstrated by ictal diffusion-weighted MRI during prior TIA in a patient with cerebral infarction]

We reported a patient with transient ischemic attack (TIA), subsequently evolving to a cerebral infarction, in whom ictal diffusion-weighted magnetic resonance imaging (MRI) detected early ischemic lesion in the left hemisphere. The patient was a 30-year-old right-handed male medical doctor, who had an in-hospital episode of TIA with obtundation and right hemiparesis, which lasted for 150 minutes. Ictal diffusion-weighted MRI obtained 110 minutes after symptom onset demonstrated an area of high signal intensity in the left striatum and corona radiata, whereas T 2-weighted and FLAIR images were entirely normal. Ictal magnetic resonance angiography (MRA) showed occlusive lesions in the M 2 branches of the left middle cerebral artery. The second MRA obtained 90 minutes after resolution of the symptoms showed nearly complete recanalization of the left middle cerebral artery, suggesting that the TIA was embolic mechanism. However the patient rapidly developed similar neurological symptoms again 58.5 hours after the TIA episode, evolving finally to a completed stroke. A brain CT obtained 1 hour after the second episode demonstrated diffuse hypodense lesions in the left basal ganglia and corona radiata, and in the left temporal lobe. MRIs 3 and 7 days later displayed completed infarcts, of which distribution was consistent with that of the hypodense lesions on the earlier CT. The left middle cerebral artery remained patent on the follow-up MRAs. The patient fairly recovered and returned to his premorbid position as medical doctor with a mild residual right hand clumsiness. In this patient, ictal and post-ictal MRAs documented an occlusion and a reopening of the middle cerebral artery. The embolic mechanism remains unknown despite detailed cardiac, vascular, and hematological examinations. In addition to recurrent embolism, we would like to point out that the reperfusion injury, secondary delayed neuronal death, and other factors may be involved in the second exacerbation evolving to the completed stroke.     

Carbon disulfide vasculopathy: a small vessel disease

We present the clinical manifestations of 4 male patients with acute stroke-like symptoms and polyneuropathy after long-term exposure to carbon disulfide (CS2) in a viscose rayon plant. The ages of onset of polyneuropathy ranged from 42 to 45 years with a duration of CS2 exposure between 6 and 21 years. The ages of onset of stroke were from 42 to 48 years. The risk factors for stroke including heart disease and diabetes were denied, except for smoking in 4, hyperlipidemia in 2 and hypertension in 1. At the initial visit in 1992, only 2 patients developed sudden onset of hemiparesis suggesting a lacunar stroke before the diagnosis of CS2 intoxication. Brain computed tomography (CT) scans showed low-density lesions in the basal ganglia in 2 patients, cortical atrophy in 1 and normal in 1. Brain magnetic resonance image (MRI) study disclosed multiple lesions in the corona radiata and basal ganglia on T(2)-weighted images in 3 patients and cortical atrophy in 1. After the diagnosis, they left their jobs for a CS2-free environment, and improvement of the working conditions was noted. During 5 years follow-up period, another 2 patients also developed an acute episode of stroke with hemiparesis. Brain CT and/or MRI follow-up studies in these 2 patients revealed new lesions in the basal ganglia and corona radiata. Intriguingly, a patient with previous stroke also developed new lesions in the bilateral thalami and brainstem. Carotid Doppler scan, transcranial Doppler scan and/or cerebral angiography did not show any prominent stenosis or occlusion in the major intracranial large arteries. We conclude that encephalopathy may occur in patients after long-term CS2 exposure, probably due to impaired cerebral perfusion. The lesions tend to occur in the basal ganglia, corona radiata and even brainstem, particularly involving the small-sized vessels. In addition, the cerebral lesions may progress even after cessation of CS2 exposure. Therefore, we suggest that CS2 exposure may be a risk factor for stroke.     

A case of micrographia after subcortical infarction: possible involvement of frontal lobe function

Most reports of micrographia associated with focal brain lesions have related this finding to damage in the left basal ganglia. Here we describe the case of a 68-year-old man presenting with reversible micrographia accompanied by hypophonia in the absence of extrapyramidal signs after cerebral infarction in the left subcortical region. At the time of the patient's admission, diffusion-weighted magnetic resonance imaging sequence showed the lesion to principally involve the corona radiata, with some involvement of the putamen. Neurologically, mild right-sided brachiofacial hemiparesis and grasp reflexes - a frontal lobe sign - were observed. As his micrographia and hypophonia improved, the patient's grasp reflexes improved in parallel. In addition, recovery of regional cerebral blood flow in the left frontal lobe was confirmed by single photon emission computed tomography (technetium-99 m HMPAO). The present case suggests the possibility that the function of frontal-subcortical circuit might also be involved in the production and improvement of micrographia and that micrographia and hypophonia may share a common pathophysiology.     

Clinical anatomic study of pure dysarthria

Nine patients with pure dysarthria underwent computed tomography or magnetic resonance imaging. Eight patients had infarcts of lacunar or larger size in the internal capsule: four in the superior portion of the anterior limb or adjacent corona radiata and four in the superior portion of the genu or the adjacent corona radiata. In one patient, there was a small infarct in the bulbar motor cortex. Dysarthria was transient and characterized by poor articulation in all cases. Five patients also had contralateral facial weakness, and three patients with lesions in the genu had minimal and transient involvement of the contralateral fingers. These three cases appeared to be variants of the dysarthria-clumsy hand syndrome. We submit that this syndrome should sometimes be regarded as a stroke syndrome rather than always as a lacunar syndrome.     

Reversible diffusion-weighted lesion in a TIA patient without arterial recanalization: a case report

A 70-year-old man with right hemiparesis (NIHSS score 15) was admitted to our hospital 1 h after onset. Diffusion-weighted imaging (DWI) revealed a hyperintense lesion in the left corona radiata and magnetic resonance angiography (MRA) revealed occlusion of the left middle cerebral artery (MCA). At 2.5 h after onset, his neurological deficits dramatically improved (with NIHSS score change from 15 to 2). Immediately thereafter, follow-up MRI revealed that the hyperintense lesion on DWI had disappeared, though the left MCA occlusion remained. By the end of follow-up MRI examination, his neurological deficits had completely disappeared. We report here the patient with transient ischemic attack with a reversible ischemic lesion on DWI without early arterial recanalization.     

Deterioration of hemiparesis after recurrent stroke in the unaffected hemisphere: Three further cases with possible interpretation

BACKGROUND: The concept of neural reorganization after brain damage is already well established, and many previous studies have successfully reported the translocation of the neural activation in the motor-related cortices during motor tasks using functional imaging modalities. Several primate and human studies have suggested the formation of newly reorganized tracts in the ipsilesional or contralesional hemisphere, but the mechanism for the formation of these tracts is still largely unknown. METHODS: Three acute stroke patients who presented with abrupt deterioration of their right-sided hemiparesis due to the infarcts following a recurrent stroke in the originally unaffected hemisphere were studied using magnetic resonance imaging (MRI), MR angiography and single-photon emission CT. The relationship between the neurological symptom on admission and the precise location of the new infarct was carefully investigated from the perspective of reorganization. RESULTS: Diffusion-weighted MRI showed a new subcortical infarct in the right hemisphere contralateral to the initial stroke in all patients. These new lesions involved the thalamus, globus pallidus or corona radiata, sparing the area of the internal capsule. T2-weighed MRI on admission showed an old infarct in the left middle cerebral artery territory, which had caused the original right-sided hemiparesis. CONCLUSION: It is proposed that the 'extrapyramidal' motor pathway in the unaffected hemisphere is associated with poststroke neural reorganization.     

Normal brain activation in hemiatrophy due to multiple sclerosis: a functional MRI case study

Evidence from recent functional magnetic resonance imaging studies suggests that adaptive cortical changes ('plasticity') could participate in the maintenance of function in multiple sclerosis (MS). Here, we addressed the impact of brain atrophy on the pattern of cerebral activation in an MS patient with a relapsing-remitting course. This patient showed mildly disabling hemiparesis of the left side (EDSS 2.0), and corresponding brain hemiatrophy (15% volume reduction) of the right hemisphere. The clinical syndrome was considered to result from a lesion in the corona radiata involving corticospinal fibers. Motor-evoked potential recordings confirmed substantial axonal damage to the pyramidal tract arising from that hemisphere. Irrespective of these asymmetries, normal brain activation was found for hand and foot movements for both brain sides. This demonstrates that brain atrophy itself does not necessarily induce cortical adaptive changes, even if mild disability is present. On the other hand, significantly disabling distinct clinical syndromes e.g. arising from spinal cord lesions may evoke cortical changes irrespective of brain atrophy. This issue has to be studied in longitudinal investigations.     

Prognosis and MRI after ischemic stroke of the basal ganglia.

The clinical courses and long-term prognoses in 16 young patients with infarctions of the basal ganglia were evaluated and the recent magnetic resonance imaging findings in 9 of them were examined. Only 5 of 14 patients (35%) had motor sequelae, 4 had hemiparesis, and 1 had gait disturbance. Secondary dystonia occurred in 1 patient. Magnetic resonance imaging disclosed a circumscribed lesion in the basal ganglia, as reflected by T2 high- and T1 low-intensity signals, in all patients. The abnormal region on T2-weighted images usually was more extensive than that observed on T1-weighted ones. The hemiplegic patients each had an area of abnormal intensity in the internal capsule or corona radiata with relatively high signals on the T2- and proton-density-weighted images. Mild to moderate asymmetric atrophy of the midbrain on the side ipsilateral to the stroke lesion was observed in 8 of 9 patients. The mechanism involved may be remote transsynaptic neuronal death of the substantia nigra, as well as Wallerian degeneration of the pyramidal tract.     

Atlanto-axial rotatory fixation caused by spontaneous intracerebral haemorrhage in a child

Introduction Atlanto-axial rotatory fixation is rare in children and usually associated with upper respiratory tract infection or trauma. We present a patient who developed the condition acutely as a consequence of rapidly evolving hemiplegia secondary to intracerebral haemorrhage.Case report A previously well 12-year-old boy suddenly developed left hemiparesis within 30 min. Soon after, he developed painful torticollis. On examination, a dense left hemiplegia was associated with left facial and hypoglossal weakness. On computerised tomography (CT) scan there was an intracerebral haemorrhage in the deep aspect of the right frontal lobe in the corona radiata, with extension in the ventricular system. The plain radiographs of the cervical spine, and CT scan later, confirmed the presence of C1–C2 rotatory subluxation. The haematoma was aspirated stereotactically through a burr hole, and at the same session, the subluxation was reduced by manipulation and traction of the cervical spine. The patient was treated with a hard collar. The torticollis did not recur. The hemiparesis resolved within 6 months. A subsequent magnetic resonance imaging and magnetic resonance angiography scan indicated possible arterio-venous malformation (AVM) at the site of the haemorrhage, which was confirmed with digital subtraction angiography. The AVM was surgically excised 1 year from the original haemorrhage.Discussion In the absence of any other predisposing factor, it is postulated that the acute atlanto-axial rotatory subluxation was secondary to the acute loss of muscular tone due to the acute hemiparesis. This explains that the subluxation has not recurred a year after, while the hemiparesis has completely resolved.     

A case of Foix-Chavany-Marie syndrome and crossed aphasia after right corona radiata infarction with history of left hemispheric infarction]

Foix-Chavany-Marie syndrome (FCMS) is a syndrome that presents facio-pharyngo-glosso-masticatory diplegia with automatic voluntary dissociation. Its most common etiology is stroke in the regions of bilateral opercula. We described a 75-year-old woman with FCMS and crossed aphasia. She had cerebral infarction of left middle cerebral artery territory 23 years before. At that time she had transient right hemiparesis, but no aphasia. This time, she suddenly became mute and was brought to our hospital. Neurological examination revealed severe weakness in her bilateral lower face, pharynx, tongue, and sternocleidomastoideus. She had no weakness of limbs. Her listening comprehension was moderately disturbed and handwriting was paragraphic. Her emotional facial movement was maintained despite of disturbed volitional facial movement. CT scan disclosed fresh infarction at the right corona radiata and old infarction at the left middle cerebral artery territory. In this patient, lesions at the left operculum and right corona radiata with the preserved right operculum gave rise to FCMS. This implies following possibilities: 1) the corticobulbar tract and corticospinal tract run separately at the corona radiata, 2) volitional and emotional tracts of facial movement run separately at the corona radiata. It was demonstrated that FCMS is not always caused by bilateral operculum lesions. Our patient did not show aphasia after the first stroke including left language area, but became severely aphasic after the right corona radiata infarction. Simultaneous occurrence of FCMS and aphasia after corona radiata lesion suggested that the corticobulbar tract and a tract that conducts linguistic information are running adjacently in the corona radiata. Our case suggested that restricted corona radiata lesion may cause severe subcortical aphasia and in case of additional contralateral corticobulbar tract lesion, severe dysarthria may occur.     

Basal ganglia germinoma: diagnostic value of MR spectroscopy and (11)C-methionine positron emission tomography

We herein report a 12-year-old girl with a basal ganglia germinoma who presented with right-sided hemiparesis after a minor head trauma. Magnetic resonance (MR) imaging revealed a minimally enhanced lesion involving the left putamen, thalamus, and corona radiata. The lesion showed low-signal intensity on T1-, and high intensity on T2- and diffusion-weighted imaging. The MR signal in the adjacent globus pallidum was also low on T2-weighted imaging. MR spectroscopy on the lesion showed a large lactate/lipid/macromolecule peak with a decreased NAA/Cr ratio, but no increase in the Cho/Cr ratio. However, posttraumatic infarction at the territory of lateral lenticulostriate artery was ruled out 1 month later. This was based on progression of the hemiparesis and neuroimaging results, including an increased Cho/Cr ratio and weak uptake on (11)C-methionine positron emission tomography of the basal ganglia lesion. Stereotaxic brain biopsy confirmed the diagnosis of germinoma.     

Infantile multiple sclerosis with extensive white matter lesions

A boy developed a right hemiparesis at 13 months of age which disappeared spontaneously at 19 months. Computed tomography and magnetic resonance imaging revealed extensive low-density areas with left-sided predominance in the white matter at age 17 months. The flash visual evoked potential revealed abnormal findings of wave V. At 20 months of age, paraplegia developed; as it receded 3 months later, a left hemiparesis developed. At that time, computed tomography demonstrated a new low-density area in the right centrum semiovale which disappeared at 28 months of age concomitant with the recovery of the left hemiparesis. Overall, he had experienced 3 independent episodes, 2 of which corresponded to each of the lesions depicted by computed tomography and magnetic resonance imaging. Multiple sclerosis was diagnosed at 23 months of age which is earlier than in any previously reported patient. Unlike most typical findings of multiple sclerosis on computed tomography and magnetic resonance imaging studies, our patient demonstrated extensive white matter lesions.     

Linear hyperintensity objects on magnetic resonance imaging related to hypertension

Linear hyperintensity lesions, which are sometimes recognized in the cerebral white matter on T(2)-weighted magnetic resonance (MR) images, have never been studied from the clinical viewpoint. We refer to these lesions as linear hyperintensity objects (LHOs) and have investigated them quantitatively. Twenty-six consecutive patients underwent routine 1.5-Tesla MR imaging. LHOs were found in 24 patients. We measured the width and number of LHOs at the upper corona radiata level on T(2)-weighted images (repetition time: 4,500.0 ms, echo time: 96.0 ms) using a scale loupe. The diameters were significantly correlated with the stages of hypertension (WHO classification). The LHOs may associated with the dilated perivascular spaces of cortical medullary arteries and may become an indicator for hypertensive small vessel disease.